Popis: |
Analytical and experimental investigations were conducted to study important tip clearance flow phenomena, such as leakage vortex, flow underturning, and the effect of clearance flow on blade loading and losses. A three-dimensional Navier-Stokes code was modified to include a tip clearance model. A recently designed transonic high-work turbine rotor was used as a test case. Detailed measurements were made at rotor inlet and exit planes and compared to analytical results. The comparisons included important design features, such as exit total pressure and flow angle. For tip clearance calculation, the agreement with data was improved in the near-tip region compared to calculation without tip clearance. The clearance flow phenomena, leakage vortex, flow underturning, changing of blade loading, and loss distribution were predicted. |